Macaroni Penguins Continued.........
Communication and Movement
Communication and Movement:
Macaroni Penguins communicate through many complex, ritual behaviors. They may flap their wings, nod their heads, or make loud screeching sounds; much like they do when courting. They may also bow, gesture, or preen with their fins. When these penguins are excited, they raise their crown feathers and bristle their yellow tufts. In the water, the penguins use their webbed feet to steer, and their tails as a rudder while swimming. They can reach up to 15mph, which may be helpfully when escaping from predators. When diving, there is difference in the angle in which the penguins descends, resulting in a correlation between the time spent at the bottom of the dive and the body angle at the ascend of the dive. The longer the penguin spends at the bottom, the steeper the body angle at the ascend of the dive. In contrast, the body angles of the penguins that had little or no bottom phase are much more shallow. After catching a good prey, the Macaroni Penguin stays at the bottom longer, and then travels to the top at a steep body angle. If no pray is encountered, they discontinue the dive and come back up to the surface at a shallow body angle. On land, penguins waddle rather than walk. They hold their flippers out sideways and backwards, and the weight of this makes them move from side to side, resulting in a waddle. The penguins may also use Bobogganing to get around on land. Bobogganing helps them get from where they are to where they want to be faster then if they would waddle.
Photograph by Pete and Barb
Predation and other Threats:
Adult Macaroni Penguins do not have predators on land; their only predators are at sea. In contrast, the un-hatched and young penguins do have predators on land. Though predation is fairly low, eggs may be eaten by skuas, sheathbills, and kelp gulls. Weakened chicks may also be eaten by skuas, sheathbills, and kelp gulls, in addition to giant petrels. Adult penguins are the victims of predation at sea. Leopard seals, orcas (killer whales), sea lions, and Antarctic fur seals are amongst the animals that prey on these penguins. Other threats include over-fishing, oil spills, and a change in climate. There has been a decline in the number of penguins within the last thirty years, and these threats are the leading factors resulting in the decline.
photograph by Pete and Barb
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